Signal regulated power supply



Dec. 6, 1955 L. F. MAYLE 2,726,350

SIGNAL REGULATED POWER SUPPLY Filed Jan. 9, 1952 2a NIL. l /4 /7 I EMF 5/6. W050 50uRcE AME i- (Z r INVENTOR LOU/5 E MAYLE BY 0 ATTORNEY United States Patent SIGNAL REGULATED POWER SUPPLY Application January 9, 1952, Serial No. 265,693 6 Claims. (Cl. 315-14) This invention relates to signal regulated voltage supplies, and more particularly to the regulation of high voltage supply energy wherein there is considerable change of load impedance in response to variations in signals applied to the load.

In a number of difierent installations a high voltage is required, which voltage should be maintained at a relatively high level regardless of changes in load impedance. It will be readily understood that in many cases when a load impedance decreases the voltage applied to the load may drop due to the reduced impedance drop through this load. For rectifiers and voltage doubler systems this effect is quite pronounced. In circuits, such as for television tubes, and particularly projection tubes, a very high anode voltage is required in order to secure the desired brilliance of the beam. In such cathode ray tube arrangements however, a variation in the load occurs in accordance with the variations in picture signals applied to the tube when it is used for television. As the current density of the beam is decreased the load drops. This variation in impedance will tend to cause a variation in the power supply voltage, producing undesired results.

In accordance with this invention there is provided a voltage regulating means for a load having a controllable variable impedance. This regulating means includes a source of power, a variable voltage means for coupling the source-to the load, controllable means for increasing and decreasing the impedance of the load, and means operating in response to the controllable means simultaneously therewith to correspondingly'decrease and increase the output voltage of the variable voltage means.

More especially, according to this invention there may be provided a system for maintaining a relatively constant operating voltage for an electron discharge device, the impedance of which tends to vary with changes in applied amplitude. In this system there is provided a source of energy such as alternating oscillator together with a circuit for developing the operating voltage from this energy,

for example by means of amplifiers operated in parallel and coupled together in series together with certain rectifier units for rectifying the amplified energy. An arrangement for controlling the amplitude of the energy applied to the voltage developing means is provided to controlthe voltage inversely with respect to the impedance variations of the load caused by the changes in amplitude of the applied signal.

The-above mentioned and'other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawing, in which the single figure is a schematic circuit diagram of a system incorporating a power supply regulator in accordance with this invention.

In the figure there is'illustrated a video amplifier 1 shown simply by block diagram to which video signals maybe supplied from a source 2. The output of the video amplifier may be applied to a projector tube indicat- 2,726,350 Patented Dec. 6, 1955 ed at 3 so as to vary the strength of a beam in such tube. To the projector tube 3 high voltage power is furnished across terminals 4 and 5 by means of a power supply system. The power supply system may include an oscillator 6 coupled'by a transformer 7 to an amplifier 8. Amplifier 8 may comprise a plurality of screen grid electron discharge tubes groups 9, 10 and 11. Each of these groups may comprise four tubes in push-pull parallel arrangement for the purpose of providing high power output. Three separate output filter circuits 12, 13 and 14 are provided for the respective tube groups 9, 10 and 11. These output circuit-s 1214 are coupled to resonant circuits 15, 16 and 17 which in turn are connected in series between terminals 18 and 19 so that triple the voltage normally produced by any one group will be obtained. Terminals 18 and 19 are connected to a voltage doubler unit 29 which may comprise the usual condenser resistor circuit 21 and rectifiers 22, 23-. At the output terminals of this voltage doubler 20 appears the supply voltage for tube 3 at terminals 4 and 5.

It will be clear that as the signals applied to the grid or beam control electrode of tube 3 are varied there will tend to be a variation in the potential between terminals 4 and 5. In order to compensate for this variation in impedance a portion of the video signal output from amplifier 1 is supplied over lead 24 coupling condenser 25 and rectifier unit 26 to the control grid 27 of electron discharge device 23 which may be a tetrode as shown in the drawing. The anode 29 of the electron discharge device 28 is couplied by means of a lead' 30 to screen grids in each of the tubes 9, 1t) and 11 of amplifier 8. The anode supply voltage for electron discharge device 28 is furnished over a regulating circuit comprising a resistor 31 and a pair of discharge lamps 32 so that the anode and screen grid voltage of this tube are regulated. A variable impedance such as lamp 33 may also be connected in the anode supply path for device 29.

It will be apparent that with the arrangement shown the screen grid voltage on the amplifier tubes 9, 10 and 11 varies with the video signal as does the impedance of the load provided by projector tube 3. However, the variation applied to electron discharge device 28 at control grid 27 is such as to vary the bias on the screen grids of the tubes in groups-9,, 10 and 11 so that the amplification provided will be increased whenever the impedance changes tend to decrease the voltage between terminals 4 and 5. Thus a regulation effect is provided which tends to maintain the potential drop between points 4 and 5 substantially constant despite changes in impedance due to variation in applied signal energy.

It will be readily apparent that the example used in the above description contribues simply one manner in which the principle of this invention may be applied for producing the desired voltage variations.

The large numbers of tubes and several stages of amplification illustrated are not necessary to the performance of a circuit in accordance with this invention although they may be desirable for the purpose of obtainingvery high voltages and relatively large current. Moreover, the use of tetrodes or other screen grid tubes, is not essential. It will be clear to those skilled in the art that triodes may be used and the changes in bias then may be applied to the control grid or other electrode to vary the gain of the amplifier. It will also be understood that the principles of this invention are not limited to regulation of extremely high voltages, as in the case of projection tubes, but apply equally well to compensation of voltage changes of a supply source due to signal produced changes in a load impedance.

While I have described above theprinciples of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and-not as a limitation to the scope of my invention as set forth inthe-objects thereof-audio the accompanying claims.

What is claimed is:

1. In a power supply andvoltage regulator system for acathode ray tube comprising a source of signals, a cathode ray'tube having a'cathode electrode, a beam control'electrode andan accelerating anode electrode, means for applying signals fromsaid sourceto said beam controlelectrode, a source of alternating electric energy, an amplifier, means for applying energy from said source to said amplifier, an'output circuit for said amplifier, means for-rectifying the voltage obtained from'said amplifier, and means'for applying the rectified voltagebetween the anode and cathode electrodes of said cathode ray tubes, a system forregulating the'voltage applied to said anode and cathode electrodes comprising a biasingcircuit connected to "said amplifiers, a regulating tube comprising a cathode, control grid, screen grid and anode with said biasing ciredit and the cathode connected to a commn reference potential source, means for rectifying a portion of said signals, and-means to apply said rectified signals'to said control grid, whereby the amplification of said amplifier .is varied inversely with said video signal.

'2. Ina .power supply and voltage regulator system for a cathode ray picture display tube comprising a source of video signals, a cathode ray tube having a cathode electrode, a beam control electrode and an accelerating anode electrode, means for applying video signals from said source to said beam control electrode, a source of alternating electric energy, a grid controlled amplifier, means for applying energy from said source to said amplifier, an output'circuit for said amplifier, voltage doubling means for rectifying and doubling the voltage obtained from said output circuit, and means for applying the doubled voltage between the anode and cathode electrodes of .said'cathoderay tubes, a system for regulating the voltage applied to said anode and cathode electrodes comprising a normal biasing circuit connected to said amplifier control grid, a regulating tube comprising a cathode, control grid and anode with the anode connected to the controlgrids of said amplifierand the cathode connected to a common reference potential source, means for rectifying a portion of said video signals, and means to apply said rectified video signals to said regulating tube control grid, whereby theamplification of said amplifiers is varied inversely with said video signal.

.-3.. In a power supply and voltage regulator systemfor a cathoderay picture display tube comprisinga sourceof video signals, a cathode ray tube having a cathode electrode, albeamcontrolelectrode and anvaccelerating anode electrode, means for applying video signals from said source to said beam control electrode, a source of alterhating electric energy, a plurality of gridcontrolled amplifiers, means for applying energy from said-source .to said amplifiers, individual output circuits. for 'each of said amplifiers, means coupling said output circuitsin-series, voltage doubling means for rectifying and doubling the voltage. obtained vfrom said, series coupled circuits, and means for applying the doubled voltage between the anodeandcathode.electrodes of said cathoderaytubes, a system. .for regulating the voltage, applied to said-anode and cathode electrodcscomprising a normal biasing circuityconnected .to said amplifier control grids, a voltage divider comprising a resistor and glow discharge lamps in series connected to said biascircuit, 'a regulating tube comprising a cathode, control grid, screen grid and anode with the anode connected to the control grids of said amplifiers,its screen grid connected to thejuncture of said resistor and said glow discharge tubes and the oathode connected .to a common referencepotentialsource, means 'for rectifying a portion of said video :signalsnand means to apply said rectified video signals to saidregulating tube control grid, whereby the .amplificationof said amplifiers is varied i inversely with said video signal.

4. In a power supply and voltage regulator system for a cathode ray picture. display tube .comprisingasource of video signals, a cathode ray tube having a cathode electrode, a beam control electrode and an accelerating anode electrode, means for applying video signals from said source to said beam control electrode, a source of alternating electric energy, a plurality of screen grid amplifiers, means for applying energy from said source to said amplifiers, individual output circuits for each of said amplifiers, means coupling said output circuits in series, voltage doubling means for rectifying and doubling the voltage obtained from said series coupled circuits,-and means for applying the doubled voltage between the anode and cathode electrodes'of said cathode ray tubes, a system for regulating the voltageapplied to said anode and cathode electrodes comprising a normal biasing circuit connected to the screen grids of said amplifiers, a regulating tube comprising a cathode, control grid, and anode with the anode connected 'to the screen grids of said amplifiers, and the cathode connected to a common reference potential source, means for rectifying a'portion of said video signals, and means to apply said-rectified video signals to said control grid, whereby-the amplification of said amplifiers is varied inversely with said video signal.

5.1m a power supply and voltage regulator system for a cathode ray picture display tube comprising a source of video signals, a cathode ray tube having a cathode-electrode, a beam control electrode, and an accelerating anode electrode, means for applying video signals from said source to said beam control electrode, a source of alternating electric energy, a plurality of screen grid amplifiers, means for applying energy from said source to said amplifiers, individual output circuits for each ofsaid amplifiers, means coupling said output circuits 'inseries, voltage doubling means for rectifying and doubling the'voltage obtained from said series coupled circuits, and means for applying the doubled voltage between the anode and cathode electrodes of said cathode ray tubes, a system for regulating the voltage applied to said anode and cathode electrodes comprising a normal biasingcircuit connected to-the screen gridsof saidamplifiers, a voltage-divider comprising a resistor and glow discharge lamps in series connected to said bias circuit, a regulating tube comprising a cathode, control grid, screen grid and anode with the anode connected to the screengrids of said amplifiers, its screen grid connected to the juncture of said resistor-and said glow discharge tubes and the cathode connected to-a common reference potential source, means for rectifying a portion of said video signals, and means to apply said rectified video signals to said control grid, whereby the amplification of said amplifiersis'varied inversely with said video signal. I

6. A'power supply and voltage regulator system for a cathode'ra-y display'tube comprising a source of video signals, a cathode -ray tube having a cathode electrode, a beam control electrodeand an accelerating anode electrode, =meansfor applying video signals from said source to said beam control electrode, a source of alternating electric energy, apluralityof screen grid amplifiers, means for;applying energyfrom said source" to said amplifiers, individual output circuits for each of saidamplifiers, means coupling said output circuits in series, voltage doubling means for rectifying and doubling the voltage obtained from said series coupled circuits, means for applying the doubled voltage between the anode and cathode electrodes of said cathode ray tubes, a normal biasing circuit connected to the screen grids of said amplifiers, a voltage divider comprising a resistor and glow discharge lamps in series connected to said bias circuit, a regulating tube comprising a' cathode, control grid, screen grid and anode with the anode connected to the:screen grids-of said amplifiers,its screen gridconnected to 'the. juncture ofsaid resistorand saidgl'owdis charge tubes .and' the cathode connected to. a common References Cited in the file of this patent UNITED STATES PATENTS 2,276,455 Beers Mar. 17, 1942 10 6 Malling Nov. 24, 1942 Barnard et al Mar. 25, 1947 Meagher May 29, 1951 Kell July 3, 1951 Little Dec. 9, 1952 OTHER REFERENCES Proceedings of I. R. E., vol. 36, page 406, March 1948. 

